The baboons received complete deafferentation of medical basal hypothalamus (MBH) in 1975. The following summary was obtained. 1. The medial basal hypothalamus (MBH) itself cannot maintain the normal periodicity of LH surge without the assistance of the other region of CNS, possibly the rostral hypothalamus. 2. The MBH is capable of releasing LH under the influence of estrogen. 3. Regeneration occurs in the MBH neurons, but the MBH cannot maintain the normal menstrual cycles. 4. The results of this experiment was presented at FASEB meeting in 1980.